Oil well packing head



June 27, 1939- F. STONE ET AL OIL WELL PACKING HEAD Filed Aug. 24, 19564 Sheets-Sheet l Inventor: J iederick Sfon .Hlberl L.S0ne.

Attorney.

June 27,

1939. F. STONE ET AL OIL WELL PACKING HEAD Filed Aug. 24, 1956 4Sheets-Sheet 2 lflvenians. fiederidlrfitone. eri L. tone.

F, STONE 51' AL 2,163,813

HEAD

June 27, 1939.

OIL WELL PACKING 4 Sheets-Sheet 3 Filed Aug. 24, 1936 Patented June 27,1939 UNITED STATES PATENT OFFICE OIL WELL PACKING HEAD Frederick Stone,Torrance, and Albert L. Stone,

Palos Verdes Estates, Calif., assignors to Hydrii Company, Los Angeles,Calif" a corporation of California.

Application August 24, 1936, Serial No. 97,632 17 Claims. (Cl. 180-14)This invention has to do with oil well packing tlon. For purposes ofdescribing certain aspects heads, used for the purpose of sealing arounddrill of the invention, as will later appear, the packing pipe or otherwork extending through the head head in this view is shown to take adrive stem of into the well pipe, and particularly with improvepolygonalcross section. ments in packing heads 01' the type disclosed in Figs. 4and 5 are sectional views taken on lines Patent No. 2,038,140, issuedApril 21, 1938, on 4-4 and 55, respectlveiy,of Fig. 3;

Packing head, and in our copending application, Fig. 6 is a fragmentaryenlargement of the check Ser. No. 50,482, filed November 19, 1935, onPackvalve in the vent passage leading from the chaming head. ber abovethe main packer; l0 In the present type of packing head, a radiallyFigs. 7 and 8 are fragmentary enlarged views m contractible packer ispressed into engagement showing a portion of the indicator mechanism inwith the work by a contracter, preferably in the changed positions; formof a piston, that is movable vertically within Fig. 9 is a sectionalview showing another form the housing. Various aspects of the inventionof packing head embodying the invention; and l are convenientlyapplicable to packing heads of Fig. 10 is a fragmentary enlarged view ofthe a this type in which the packer contracting piston is indicatorpiston in Fig. 9. actuated by fluid pressure, although it is to be Inthe typical and illustrative form of the understood that in certain ofits broad aspects, the invention shown in Fig. 1, a pa 0! Packing headsinvention is not to be regarded as limited to pack- Ill and H are shownto be mounted in tandem ing heads in which the packer is pistonactuated, arra t a e th w p p or casing the or, where a packer actuatingpiston is used, to one individual packing heads and their connectionsoperated by fluid pressure. Without going into forming a general headassembly l3 adapted to detail at this point, it may be stated that themaintain a fluid tight seal about the drill pipe or main objects of theinvention are directed to other Work during drilling Op t ons. OI Whileimprovements in the packer construction and e p p is going into 011% Ofe We 8-11 in the mounting, adjustable stop control means for the mannerlater to be described in detail. Heads l0 packer contracting piston, andt ariou 1 and II, while generally similar, have certain difprovemcnts inthe construction, arrangement and ferences in construction and operationthat adapt control of packing heads in tandem arrang ent. them t theirparticular functions in e p operating to maintain a fluid tight sealabout the tion of the head assembly 3- In des the work as it is beinglowered into or withdrawn from construction of the two packing heads,reference 80 the well. first will be made to their common structural Allthese generally stated purposes of the invenfeatures, using the samereference characters for tion, as well as various other features andobjects, corresponding parts, and then to the structural will be mostreadily understood and explained to aspects in which the heads aredifferentiated. best advantage without further preliminary dls- Thelower head II is attached to the well cascussion, from the followingdetailed description of me l2, and upp r hea to a P l4 intercon- Lhcinvention in one of its typical and preferred fl e g e tWO heads, y upngs l5 havin forms. Reference is had throughout the descripthreaded boxends l5a receiving the threaded ends m tion to the accompanyingdrawings, in which: of the pipes. Each packing head comprises a 0 Fig. 1is a general view, in elevation, showing a tubular b y us ng It hav g aower reduced typical emb diment of the invention ri i diameter bore I1and a counterbore it, there being pair of packing heads in tandemarrangement, a downwardly tapering shoulder I9 between the certain ofthe connections therewith being shown two bores. A tubular head 20having a bore 2| diagrammatically; and a threaded counterbore 22, isthreaded at 21 5 Fig. 2 is a longitudinal sectional view of the into theupper end of the housing. Although the upper packing head illustrated inFig. 1, the. main head 29 i5 apfl 0f Vertical l t e 1! packer beingshown in radially constricted posiany reason such adjustment is founddesirable, it tion; I will ordinarily be screwed fully down to seat onFig. 2a is a fragmentary section as viewed on body shoulder 24. Fluidleakage from within the 50 line lit-4a of Fig. 3, but showing the packercom housing aroun the head is Prevented y ab e pressed into engagementwith the flat surfaces of means, such as a packing ring 25. the drivestem; The tubular head 20 conveniently provides a Fig. 3 shows the lowerpacking head in longimounting for a radially compressible rubber tudinalsection, with the packer in released posipacker 26 preferably in theform of a continuous 5 annular sleeve normally having a substantiallyuniform diameter bore 21 with beveled surfaces at 28 and so, see Fig. 3,an outer and upper cylindric surface ill, and a downwardly tapering orconical surface ll. The upper end of the packer sleeve is supported bythe lower tubular portion of the head 20. One of the important featuresof the invention is an improved connection between the support andpacker that will withstand, without damage to either the connection orpacker, the various distortions to which the latter may be subjectedunder conditions of operation under high pressure. As illustrated inFig. 2. the packer sleeve in its constricted condition. is deflectedinwardly about the work, for example the drill pipe 82. Under extremewell pressures, the packer may be forced upwardly within space 33between pipe 32 and the bore II, a distance considerably above theposition shown. The result is that the packer is subjected to severeshearing stress at the lower edge Ila of bore 2!, as well as to aninward radial strain tending to shear the upper surface 28a of thepacker from its mounting. This inward radial distortion of the upper endof the packer extends, though to a progressively lessening degree, toits outer periphery. Thus the radially inward deflection and distortionof the packer resulting from its being forced up into the space 33, isleast within the outer portion indicated at N.

The packer mounting, generally indicated at 35, comprises a ring I thatpreferably is removably attached to the tubular head 10 by suitablemeans, as for example by pins 31, see Fig. 5, inserted within bores llextending through the ring and intersecting the head Ill. As will beapparent, these pins may be driven out of the bores to disconnect thering II. The packer 26 is connected to and suspended from the mounting35 by a continuously annular fabric material 39. which may be formed inmultiple ply or by a suitable number of separate fabric layers, embeddedwithin the packer and extending downwardly and inwardly within therubber at the outer portion 84. The upper and inwardly turned portion ofthe fabric is clamped between ring I and ring ll attached to the formerby screws I. The top surface Ila of the packer bears against the bottomsurfaces of ring it and head 28 which are provided with annular ridges,and into the spaces between which the rubber flows when the packer issubjected to upward compression. These ridged surfaces of the ring andhead act to form an extremely strong bond with the packer for the reasonthat as the rubber is forced into the inter-ridge spaces, the air isexpelled from the spaces, and thereafter the fluid pressure in the headtightly holds the rubber to the metal surfacm. An annular, double lippedpacking 42 prevents any fluid that might leak outwardly between thelower end of head 20 and the packer. from escaping past ring 36. Thepacker sleeve is internally reenforced at its upper end by suitableflexible reenforcing material, preferably layers of fabric 43, embeddedin the rubber and extending horizontally inwardly and then downwardlybelow the bottom of surface ll.

As will be understood from the foregoing, the fabric It connecting thepacker with the mounting is advantageously positioned to withstand themost severe usage and distortion of the packer, by reason of its beingembedded in the outer portion ll of the rubber at which the leastdeflection and distortion of the packer occurs. Tear-- ing and strippingof the rubber from the packer, as might otherwise result from rotationof the drill pipe with the packer rubber forced upwardly in space I8, iseffectively prevented by the reenforcing fabric 43, and the fact thatthe latter is extended inwardly and downwardly adjacent the packer borewhere the wear and stresses on the rubber are the greatest. We havepreviously explained how at times the combination of radial contractionof the packer and well pressure applied thereto will force the rubberupwardly within space 33 and cause greater displacement or movement ofthe rubber at the inner surface of the packer support than toward theperipheral portion thereof. The feature of locating the fabricattachment ll within the outer interior of the packer is of greatimportance in that the fabric thus is removed from the inner portion ofthe rubber subjected to greatest distortion and where the tendency ofthe rubber to become sheared from its support is greatest, with theresult that the fabric is not subjected to bending and shearing strainsthat otherwise might be suflicient to rupture it and thereby sever thepacker from its support. It will be understood that materials other thanfabric may be utilized in the arrangement illustrated, to support andreenforce the packer, although fabric is preferred because of itsinherent flexibility and rubber bonding qualities.

The packer contracting piston 45 has upper and lower portions a and Nbof diiferential diameters corresponding to the diameters of the housingbores I8 and I1, respectively, the piston having a sliding fit withinthe housing and carrying suitable packing rings 48 to prevent fluidleakage. The angularity of the intermediate tapered portion 41 of thepiston is somewhat greater than the angularity oi the housing shoulderll, so as to provide an annular space at 48 between the piston andhousing, for the introduction of pressure fluid for purposes later to beexplained. In its lowermost position, see Fig. 3, the piston seats onannular surface 50, the angularity of which corresponds to the taper ofthe piston surface 41.

The contracter 4! has a bore ll of substantially the same taper assurface 3! of the packer, so that as the contracter moves upwardlyrelative to the packer, it acts to constrict the latter radially inwardagainst the work 32. The relative positions of the contracter 45 andpacker 28 in constricted condition, are illustrated in Fig. 2, whereinthe rubber is shown to be compressed against the pipe 32 with the upperbore surface 28, beveled to prevent tearing, of the packer forcedinwardly at the bottom of space 31.

The lower depending portion of the tubular head 20 is spaced at 53 fromthe wall of the housing to provide an annular chamber containing a ring54 that is attached to the contracter piston and forms with it, what maybe termed the piston assembly. As illustrated in Fig. 5, ring 54 isdetachabiy secured to the top of the contracter piston, by means ofremovable pins 55 inserted within open end bores 58 terminating inpiston ll and intersecting ring 54. The latter carries suitable packingmeans 51 sealing the piston against downward fluid leakage. The purposeof ring ll primarily is to communicate to piston 45 the pressure offluid introduced to chamber 53, as will later be explained. It willsuflice to state at this point that as a result of fluid pressureapplied to ring 54, the contracter I is moved downwardly from theposition c! Fig. 2 to that of Fig. 3, to release the packer from thework. A vent passage II is formed in the upper portion of the contracterI for the purpose oi releasing irom space ll below ring Bl, anyoperating fluid that might leak past the piston into space 8| andotherwise tend to resist downward movement or the piston assembly. Ventpassage II communicates at its lower end with chamber II and with spaceit by way of port ill, see Fig. 8, controlled by a spring pressed checkvalve ii. The valve unseats to pass fluid from space SI into chamber llas the piston assembly moves downward, and at other times is held inseated position by the spring 62 to prevent return flow or the pressurefluid from chamber 49.

Adjustable stop means, generally indicated at 63, is provided for thepurpose of limiting the upward travel of the piston assembly, and alsoto limit the degree to which the packer is constricted about the work inthe uppermost position of the piston, independently of the amount offluid pressure being exerted upwardly against the piston to compress thepacker. In one form the adjustable stop means comprises a plurality ofcircularly arranged set screws 64 extending through the head and apacking retaining ring into space 53. Individual packing rings 8 preventleakage of the high pressure fluid around the set screws. Normally,screws 64 will be set to limit the upward travel of the piston assemblyat a point to which packer 26 will be constricted about the work withsufllcient tightness to prevent any considerable upward leakage offluid, but at the same time to permit just enough fluid leakage throughthe packer to lubricate its engagement with the work. This type oradiustable piston stop is disclosed in the earlier flied applicationreferred to above. The present invention constitutes an improvement inthe stop means in that it provides means for the simultaneous adjustmentof all the individual set screws 54, as by the adjustment or any one ofthem, thus obviating the necessity for adjusting each set screw, andassuring that the screws will be adjusted to exactly the same verticalpositions.

Each of the set screws 84 carries a sprocket 68 meshing with acircularly continuous chain 89, see Fig. 4, contained within andtightened against the base of an annular groove l0 formed within ringsII and 12. These rings are secured together by screws 13 and aresupported on the annular shoulder 14 of a ring 15 resting on sprockets58 and through which the upper ends of the set screws project. Rings Iiand I! serve as a floating carrier for the chain 6!, the rings in thelower head H extending loosely about the pipe I4 and similarly, in theupper head ill, about a nipple l6 threaded into counterbore 22 of memherI'll. As will be apparent, by adiusting any individual set screw Bl, allthe other set screws whose sprockets 88 are meshed with the chain 69,are correspondingly adjusted in the same direction and to the samedegree.

The upper head It is constructed to operate automatically as a blow outpreventer, and in this respect its structure differs in certain respectsfrom the construction of the lower head i i. The packing contracterpiston 45 in the upper head is made automatically responsive to suddenincreases in the well pipe pressure so as to auto matically constrlctthe packer about the drill pipe, by means of a second packer, generallyindicated at 18, carried within the lower portion of the piston 45. Thislower packer ll preferably will be made to maintain a fairly tight fluidseal between the piston 45 and the drill pipe, although some leakagepast the packer ll may occur without disturbing its eirectiveness as ablow out preventer, since the packer and constrictor assembly willnecessarily be actuated when a blow out occurs, because oi the greatvolume or well fluid released under high pressure. Thus packer I8 servesprimarily to provide sufliclent seal or restriction about the work thatwill cause a more or less sudden increase of fluid pressure in the pipeII to raise the piston l5 and constrict the upper packer 26.

Packer I8 comprises a rubber sleeve vulcanized to an outer cylindrictube ll inserted within the piston counter-bore t2, tube ll havingclearance at I from the bore wall and at 8 from the shoulder at the topof the counterbore so as to be freely rotatable together with thepacker, within the piston. The packer is supported on a retaining ring84 threaded into the lower end of bore 82 and held in place by set screw8. The bottom or the packer extends outwardly below the lower end oftube Bi and is provided with an annular lip "2 adapted to be forcedoutwardly by fluid pressure into sealing engagement with the wall ofbore 82. The packer 80 is moulded about a perforated reenforcing metaltube iii, the rubber filling the tube perforations 85a to eflectiveiyintegrate the metal tube with the rubber body in such manner that theformer will hold the rubber from flowing" or gathering as the pipecollar 32a passes through. The rubber packer 80 has an inwardlyprojecting annular lip 86 engaging the outer surface of the pipe andhaving a downwardly inclined upper surface 81 and a lower substantiallyflat or slightly inclined suriace 88.

It is desired to taper the top surface 81 of the packing lip in order tofacilitate downwar passage of the pipe collar through the packingagainst pressure in pipe It. By virtue of its shape, lip 85 isreenforced against and made relatively resistant to upward deflection byfluid pressure or by the pipe collar, so as to effectively withstand anysevere conditions of wear that might result from repeatedly pulling thecollars through it as the pipe string is elevated. The packer liphowever offers less resistance to downward movement of the pipe collarsthrough it,

since the lip will more readily deflect in a down direction. Uponengagement by the collar, the lip is doubled upwardly or downwardly, inaccordance with the direction of collar movement, into the spaces at 89and 90 proportioned to afford ample clearance between the packing andcollar to accommodate deflection of the lip.

The lower packing head II is provided below the piston 45 with avertically movable pipe contacting means, generally indicated at 9|,that operates as a part of a signalling system for indicating the upwardpassage of the pipe collars Ila past a predetermined pont below thepacker constricting piston, during withdrawal of the drill pipe from thewell. The vertically displaceable means indicated at BI is to beregarded merely as typical of various suitable devices that are upwardlydisplaceable upon engagement by the pipe collar, and capable ofactuating the later described parts of the signalling system. In itspreferred form, the device 9! comprises a cylindric ring 9! slidablyengaging bores 94 and 95 of the head and coupling I 5, respectively, andhaving its outer surface channeled at 93 to reduce frictional contactwith the bore walls. Normally, and

in its lowermost position, ring 92 seats on an 75 annular shoulder 90,the ring assembly being shown elevated from its seat in Fig. 3 merelyfor purposes of illustration and description. Clamped between the upperportion 92a of the ring and a retaining ring 91 threaded into its lowerend, is a perforated tube 90 carrying a plurality of circularly spacedrubber lugs 98 molded integrally with the tube and project'ng inwardlyto an extent that they will be engaged by the pipe collar 320 as thedrill string is elevated. Preferably, in order to prevent the ring frombecoming untimely raised as a result of contact between the rubber lugsand the pipe between couplings, the lugs will have the maximum clearancefrom the outside surface of the pipe 32 (assuming the work in Fig. 3 toconsist of a circular drill pipe), that can be maintained and yet havethe lugs engaged by the pipe collar with suflicient tightness to raisethe ring. Rings 92 and 91 may contain circularly spaced openings I00 andIM to provide space, in addition to the spaces between the rubber lugs,for fluid to pass through the ring without the fluid flow beingrestricted to the extent that the ring assembly will be elevated byfluid pressure alone. In case the pipe is rotating with the collar inengagement with the lugs, tube 98 and the lugs, or the entire ringassembly, may rotate within the housing.

Upward movement of ring 92 past a predetermined point operates asuitable signal actuating device, typically of the character indicatedgenerally at I02, and shown in detail in Figs. 7 and 8. The device I02comprises a laterally displaceable tubular piston I03 including anenlarged diameter head portion I04 contained within the housing boreI05, and a tubular stem portion I06 movable longitudinally within thebore of fitting I01 threaded into the housing counterbore I08. Thepiston head I04 contains a check valve I00 which is normally seated bycoil spring IIO to prevent leakage through opening III of the pressurecommunicating fluid contained in the signalling system. The pistonnormally is thrust outwardly to project the rounded end of the head I04into the housing bore 90 by coil spring II2, the inward position of thepiston being determined by engagement of the enlarged end lIIGa of thehead with shoulder Ill at the end of the fitting bore H5.

The lateral or vertical pressure acting against the piston I03 isbalanced by communicating the well pressure via space I030 and openingI03b, to annular grooves I03a in the piston, the groove at the left alsoconnecting opening I031) with chamber I03d.

The fitting I01 is connected with a suitable pressure indicator or gageIli, see Fig. l, by pipe 1, and the pipe, fitting and piston I00, allare filled with a suitable pressure communieating fluid, for example arather heavy but flowable oil, so that outward displacement of thepiston from the position of Fig. 7 to that of Fig. 8, will develop fluidpressure in line III that is indicated by the gage Hi. The system may becharged with the oil in any suitable manner, as by introducing the oilthrough a fitting IIO below the gage, and holding the check valve I09open with the piston positioned as in Fig. '7, until oil dischargesthrough opening ill, indicating that all the passages between the valveand gage are filled with oil. Preferably, line III will be charged withfluid at a pressure greater than the casing fluid pressure, to insureagainst the piston being forced outwardly by the well pressure. Shouldthe fluid pressure in the signaling system tend to drop below wellpressure, check valve I09 will open to balance the pressures. Figs. 7and 8 indicate the two positions of the indicator piston I03 before andafter engagement by the outwardly inclined surface 921; of the ring 92,as the latter is elevated by the engagement of collar 22a with therubber lugs 99. As the ring moves up, surface 921) cams the piston I03to the position of Fig. 8, developing a pressure in line III that isindicated on the gage IIB. Ring 92 is limited in its upward position ofFig. 8 by engagement with suitable stop means, for example circularlyspaced screws S projecting into the housing bore 24 at a levelpermitting cam surface 92b to travel upward while in engagement with thepiston, a distance sufficient to cause the piston to communicate apressure impulse, but limiting the upward travel of the ring assembly sothat after the pipe collar has passed through, the piston still willengage the cam surf ace. Thereupon, the ring assembly may drop bygravity to its lower position.

Referring now to Fig. l, the upper and lower packing heads areinterconnected by tie bolts B 20 in the lower packing head. The packercontracting pistons in the heads I0 and II are operated by pressurefluid that may be derived from any suitable source via line H9, or fromthe well casing I! through line I20. The pressure fluid is supplied tothe piston chambers in the two heads via line I2I which is communicable,under control of a four way valve I22, with chambers 53 and 49 in theupper head I0 via pipes I23 and I24, respectively, and with thecorresponding chambers in the lower head II by way of lines I26 and I26,under control of four way valve I21. As the contracter pistons are movedvertically, fluid from one or the other of chambers 49 and 53, dependingupon the direction of piston movement, is exhausted through lines I28and I29.

Referring to Fig. 2, it will be noted that the piston assembly,including piston 45 and ring 54, provides an upwardly facing pressurearea, the top surface of ring 54 exposed to chamber 53, and twodownwardly facing pressure areas, the tapered surface 41 of piston 45.and the lower end of this piston including the area of packer 18 betweenthe bore of the retaining ring 04 and the outside of pipe 32. Thesepressure areas. of the piston assembly may be conveniently designated inthe order named, as P1, P2 and P3. As illustrated, the combined areas ofP: and P3 is greater than the area P1. but P1 is greater than either P2or P3, although it is only of importance that P1 be greater than P3.

Advantage is taken of the differential pressure areas of the pistonassembly as a means whereby the packer 26 may be released from the work,while at the same time releasing movement of the contracter is resistedby the fluid pressure within the casing I2 acting against pressure areaP3 of the piston. Referring to Fig. 1, assuming line I2I to be incommunication with line I20 connecting with the casing, by reversing theposition of valve I22 to connect the discharge pipe i20 with space 49via line I24, the well pressure is applied through line I23 and chamber53 against the upper pressure area P1 of the piston assembly. As statedbefore, the area Pi is greater than P3, and with the pressure exhaustedfrom space Ill, the unbalanced pressure on areas Pr and P; results indownward movement of the contracter and release of the packer 26 fromthe work.

As will be understood, only a single packing head may be used tomaintain a seal about the work and to serve as a blow out preventer,without necessitating the use of the illustrated dual tandem arrangementthat has the added utility of enabling a seal to be maintained whilelowering or removing the drill pipe. To illustrate the operation of asingle packing head, for example the upper head III, the packer in thelower head may be assumed to be released from the drill pipe and valveI30, Fig. 1, closed to render the lower head inoperative. To illustratethe operation of the upper head when the well starts to flow, as forexample during drilling or at any other time when the packer "normallyis open, assume the parts to be in the positions of Fig. i

I with valve IBI closed and valve I32 opened, the

pipe II! to be connected with a source ofpressure fluid, for examplewith the circulating fluid pumps, .not shown. Valve I22 is thrown to theposition illustrated to communicate the pressure fluid to chamber l9 andto relieve pressure from chamber 52 above the piston. With the packer inthis position, the pipe 32 may be rotated and moved back and forthbetween the collars during the operation of conditioning the circulatingmud in the well to the point where the flow is under control. Then thepacker may be released by reversing valve I22 to communicate the fluidpressure to chamber 53 and ex- .haust the pressure from chamber it. whenthe packer contracter is independently controlled and operated by fluidpressure from line H9 as just explained, the lower packer 18 need notnecessarily be used, as the operator has full control in the event ofsudden development of pressure in the well.

Fig. 3 illustrates the adaptability of the piston actuated packer toseal about work of polygonal cross section, for example an octagonaldrive stem or kelly 32b. The packer also is capable of sealing aboutdrive stems of other cross sectional shapes, the octagonal form beingshown as typical. The fact that our improved packing head can maintain asubstantially fluid-tight seal about a polygonal cross section drivestem rotating within the packer, is of great advantage and importance inthat the necessity for the usual relatively complicated and expensivedevices employed to seal of! around the drive stem, is obviated in favorof a single and relatively simple packer sleeve capable of sealingaround allowing a restricted leakage of fluid through the packer tolubricate its engagement with the drive stem surfaces. Lubrication isessential in i order for the rubber to withstand the wear and the packerabout the drive stem, pressure fluid is introduced to chamber 4!,causing the piston to raise and constrict the packer into engagementwith the flat surfaces of the drive stem as shown in Fig. 20. Movementof the piston in a packer contracting direction, and therefore theextent of packer contraction, are limited by proper adiustment or stopscrews 84, to permit a slight upward leakage oi well fluid through thepacker for the purpose, as stated, of lubricating its contact with thedrivestem. Tests have demonstrated that under these conditions, thepacker is capable of maintaining, except for the slight leakage, a sealabout the drive stem over long periods of operation.

To understand the operation of the two packing heads Ill and II, assumethat the drill pipe 32 is being pulled from the well, and that thepacker 26 in the upper head is closed about the pipe as shown in Fig. 2,with the packer in the lower head in the released position of Fig. 3.Assuming the well to be under pressure, valve I32 may be closed andvalve Ill opened to supply pressure fluid to line I2i from the casingI2. Generally speaking, the two packing heads are operated to passsuccessive pipe couplings 32a without loosening the fluid seal aroundthe pipe, by keeping the upper head I! closed until the coupling passesabove the packer 26 in the lower head II, after which the latter isclosed and the packer in the upper head opened, to permit the collar topass on through. The described signalling system is used to control theoperation of the heads, since it indicates the position of the pipecollar with relation to the lower packer and enables the operator todetermine when the coupling has passed through the lower packer, so thatthe latter may be closed and the upper packer opened.

Thus, as the collar 32a engages and elevates the ring assembly 9|, thesignalling system indicates the position of the collar by pressureincrease on the gage Iii resulting from outward displacement of thepiston I03, all in the manner previously explained. By observing themovement of drill pipe extending above the upper head III the operatoris able to visually gauge the distance that the coupling 22a must travelto move up through the packer in the lower head. At that point, valvesI22 and I21 are reversed, causing the packer in the lower head to closeabout the pipe below the coupling, and the packer in the upper head toopen for the purpose of passing the coupling.

As will be understood without the necessity of further and repetitiousexplanation, the upper and lower packing heads are operated in areversed sequence while drill pipe is being lowered into the well. Asthe pipe goes into the well, the position of the coupling with relationto the packer in the upper head, is gauged by reference to the topportion of the housing, the described signalling system being used onlyduring withdrawal of the pipe.

Fig. 9 shows a variational form of packing head similar in generalrespects to the type illustrated in Fig. 3, but differing principally inthe particular form of piston stop adjusting means, the arrangement,relative to the packet, of the signal actuating device, and theconstruction of the main packer. Parts that are the same as thosepreviously described are given the same reference characters. In thisvariant form, the vertically movable stop pins I35, slidablelongitudinally within bores I38 in the head 20', are adjustable by meansof a rotatable ring I21 provided with sockets I38 to receive amanipulating tool, and threaded at I55 on an upper tubular extension Iof the housing screwed into bore I of member 25. The housing extensionI45 has an interior work centering flange I42 presenting a downwardlyand inwardly inclined surface I43, and a bottom shoulder I44 that servesas a stop for the signal actuating ring assembly I45. The upper ends ofpins I35 are received within an annular groove I45 in the bottom face ofring I31.

In the drawings, the stop pins I35 are shown to be maintained in raisedposition by frictional engagement with the individual packers I41, Aswill be apparent, by rotating ring I31, the stop pins may be maintainedin diiferent but corresponding positions of adjustment relative to thepacker and its actuating piston.

In Fig. 9, the plunger actuating ring assembly I45 is movable verticallywithin bore I45 between shoulder I44 and shoulder I49 of the head 25'.The construction 01' the ring assembly is generally similar to thepreviously described form, excepting that the packing I5Il is morenearly the internal diameter of the outer sleeve I5I, and the rubberlugs I52 have square cut under-shoulders I53 that are engaged by thecouplings as the pipe string is elevated.

The piston, generally indicated at I54, differs from the form shown inFigs. '1 and 8, principally in that the pressure of fluid in line II1,alone is utilized to maintain the plunger in its projected position, thespring being eliminated. The rounded plunger head I55 contains a boreI55 through which fluid pressure is communicated from within the housingto chamber I51; the sides of the piston being flattened at I55 toestablish open communication between the chamber and transverse boresI55 connecting with bore I55. The piston is thrust into the housing boreto a limiting position determined by the engagement of the pistoncarried lugs I with bushing IN, by fluid pressure applied at the outerend of rod I 52 sealed around by suitable packing I53. Upward movementof ring I5I by the pipe collar to position of engagement with shoulderI44 thrusts the piston outwardly, developing an indicated pressure inline II1. After the collar passes through the rubber lugs, the fluidpressure against piston rod I52 returns the piston to the positionillustrated, causing the rounded piston nose to cam ring I5I downwardly.

In Fig, 9 we have shown, in addition to the check valve 5| past whichfluid is released from chamber 59 through passage 55, a second pressurerelief passage formed by a bore I54 in portion 54 of the piston, andcontrolled by downwardly seating spring pressed check valve I55. Thissecond pressure relief passage and valve are provided as a means ofpermitting the piston to move downwardly to its lowermost position, inthe event passage 55 should for any reason become clogged against fluidescape therethrough. Assuming passage 55 to be closed, as the pistonmoves downwardly, check valve I55 will unseat and pass fluid from space55 to chamber 53 at the point at which the pressure in 55 starts toexceed the pressure in 55. The piston will then continue its downwardtravel, despite the communication between the two chambers, by reason01' the larger pressure area P1 exposed to the upper chamber.

The main packer I55 has a substantially cylindric bore I51, and anannular lip I55 projecting inwardly from the bore wall. Broadly speakinglip I58 may have any suitable shape, although preferably it is so formedthat while in engagement with the work, as it normally is, the lip ismore resistant to upward deflection than to downward deflection.Typically, the lip may be formed with an upper, downwardly and inwardlyinclined surface I55, and a lower surface "I! of comparatively lessangularity in a downward and outward direction. so as to render the lipless resistant to downward deflection. By reason of its under surfacebeing cavitated as at I", the lip is less resistant to downwarddeflection because of the removal at "I of rubber that would otherwisereenforce the lip against downward deflection. comparatively, the lip ismore resistant to upward deflection by reason of the reenforcementafforded by the rubber at I12. The outer surface of the packer has anannular cavity I13 substantially opposite the lip I55 to provide a spaceinto which the rubber may flow or expand when the packer is contracted.

Lip I55 is itself capable of providing a fluidtight seal about the pipe52, without contracting the packer from the position shown, at suchtimes as the casing pressure is comparatively low, for example not inexcess of 300 pounds per square inch. The lip is maintained in sealingengagement with the surface of the pipe by the upwardly applied fluidpressure, and by reason of its shape characteristics, the lip issufflciently resistant to upward deflection that it will hold thepressure. As the pipe contacting surface of the lip becomes worn, thepiston may be raised willciently to compensate for such wear by radiallycompressing the packer and lip, stops I35 being adjusted, if desired, tolimit the piston travel. By virtue of its reenforced characteristics,the lip will withstand repeated passage of pipe collars upwardly throughit, and, after the passage of each collar, the lip will return to itsillustrated position of sealing engagement with the pipe. As the pipestring is being lowered through the packer, the lip will deflectdownwardly to pass the collars, without becoming appreciably worn.

In the event the well develops comparatively high pressures that the lipI55 will not hold, the packer may be bodily contracted about the pipe tobring the packer bore I51 into sealing engagement therewith. Upon radialcontraction of the packer, the lip, relatively, will be forced in thebody of the packer and the rubber will expand into cavity I13 tocompensate for the lip displacement. It is important to observe thateven though the lip should be severely worn, even to the point ofseverance from the body of the packer, the latter still may becontracted about the pipe to maintain a fluid-tight seal.

We claim:

1. In a packing head for well pipe, a tubular housing adapted to takework through its bore, the walls of the housing forming a closed space,radially contractible packing in the housing and about the work, amember movable to contract the packing, a plurality of movable stopsextending within said space and engageable by said member in its packingcontracting movement, and means for adjustably moving said stopssimultaneously relative to the housing and packing and said contractlngmember.

2. In a packing head for well pipe, a tubular housing adapted to takework through its bore, the walls of the housing forming a closed space,radially contractible packing in the housing and about the work, amember movable to contract the packing, a plurality of movable stopsexenamels tending through the wall 0! the housing into said space andengageabie by said member in its packing contracting movement, and anadjustable member movable relative to said housing and maintaining saidstops in diiierent but corresponding positions of adjustment relative tothe packing and said-contracting means.

3. In a packing head for well pipe, a tubular housing adapted to takework through its bore, said housing containing a closed space, radiallycontractible packing in the housing and about the work, a fluid pressureactuated piston ior contracting the packing, means for introducing fluidto said space to actuate the piston, a plurality of movable stopsextending'within said space and engageable by said piston in its packingcontracting movement, and adjustable means movable relative to saidhousirm and operable to maintain said stops in diilerent butcorresponding positions 01' adjustment relative to the packing and saidcontracting member.

4. In a packing head for well pipe, a tubular housing adapted to takework through its bore, radially contractible packing in the housing andabout the work, a fluid pressure actuated piston for contracting thepacking, a plurality of movable stops engageable by said piston in itspacking contracting movement, and an annular and rotatably adjustablemeans coasting with.

said stops to position them in different but corresponding positions ofadjustment relative to said packing and contracting means.

5. In a packing head applied to a well pipe. a

tubular housing adapted to take an elongated member through its bore, aradially contractible packer in the housing and about the work, a packersupport, a packer contracting piston movable upwardly within the housingby fluid pressure to constrict the packer about said member, said pistonand support enclosing a chamber about the packer, means forming a fluidvent passage leading from said chamber, a check valve preventing returnflow or fluid through said passage into the chamber, and means formoving said piston vertically by fluid pressure.

6. In a packing head for well pipe, a housing, a tubular packer withinthe housing and adapted to take work through its bore. a portion of thepacker bore wail normally being spaced about the work, an annular lipprojecting inwardly from said portion of the bore wall and engaging saidwork to seal around it, and a fluid pressure actuated tubular pistonsurrounding said packer and operating to press said normally spacedportion of the packer bore wall into engagement with said work, theoutside of said packer within the piston being recessed to accommodateoutward displacement of the packer material as the packer is contractedabout the work.

7. In a packing head applied to a well casing, a tubular housing adaptedto take collared pipe through its bore, radially contractible packing inthe housing and about the pipe, means for contracting the packing aboutthe pipe, means actuated by fluid pressure for indicating verticalmovement of the pipe collar to a predetermined position relative to thepacker, and an annular pipe surrounding member displaceable verticallyby engagement with a pipe collar for actuating the last mentioned means,

8. In a packing head applied to a well casing, a tubular housing adaptedto take collared pipe through its bore, radially contractible packing inthe housing and about the pipe, means for contracting the packing aboutthe pipe, a member movable laterally by virtue 01' vertical movement ofthe pipe collar, fluid pressure actuated means indicating lateralmovement oi said member, and an annular pipe surrounding memberdisplaceable vertically, by engagement with a pipe collar for actuatingthe last mentioned means,

9. In a packing head applied to a well casing, a tubular housing adaptedto take collared pipe through its bore, radially contractible packing inthe housing and about the pipe, means for contracting the packing aboutthe pipe, an indicator, a line charged with fluid under pressure atleast as great as the well casing pressure, and means actuated by virtueof pipe collar movement for communicating pressure to the fluid in saidline, the last mentioned means including an annular pipe surroundingmember displaceable vertically by engagement with a pipe collar. A

10. In a. packing head applied to a well casing, a tubular housingadapted to take collared pipe through its bore, radially contractlblepacking in the housing and about the pipe, means for contracting thepacking about the pipe, a vertically movable annular member surroundingthe pipe and adapted to pass the pipe collar, said member being upwardlydisplaceable when engaged by the pipe collar, and means indicatingupward movement of said member.

11. In a packing hea'd applied to a well casing, a tubular housingadapted to take collared pipe through its bore, radially contractibietubular packing in the housing and about the pipe, means for contractingthe packing about the pipe, a vertically movable member surrounding thepipe, and centering the pipe relative to said packing, said member beingadapted to pass the pipe collar and being upwardly displaceable whenengaged by the pipe collar, and means indicating upward movement of saidmember.

12. In a packing head applied to a well casing, a tubular housingadapted to take collared pipe through its bore, radially contractiblepacking in the housing and about the pipe, means for con tracting thepacking about the pipe, an annular member surrounding the pipe andadapted to pass the pipe collar, yieldable means carried by said memberand engageable by a pipe collar, said member being upwardly displaceableupon engagement of said yielding means by the pipe collar, and meansindicating upward movement of said member.

13. A packing head for well pipe comprising a tubular body adapted totake work through its bore, a tubular packer, a support for one end ofthe packer, a packer contracting piston movable toward said support toaxially compress and radically contract the packer about the work, theinner portion of the packer adjacent said support being displaceable,when the packer is radially contracted, into a space between saidsupport and the work, and fabric embedded in the packer and having aprojecting end portion attached to said support, said fabric beingspaced substantially further from the packer bore than from the outsideof the packer so as to permit said displacement of the inner portion ofthe packer adjacent the support without subjecting said end portion ofthe fabric to rupture by bending and shearing strains.

14. A packing head for well pipe comprising a tubular body adapted totake work through its bore, a continuously annular packer, a support forone end of the packer, a packer contracting piston movable toward saidsupport to axially compress and radially contract the packer about thework, the inner portion of the packer adjacent said support beingdisplaceable, when the packer is radially contracted, into a spacebetween said support and the work and continuously annular fabricembedded in the packer and having a projecting end portion attached tosaid support, said fabric being spaced substantially further from thepacker bore than from the outside of the packer so as to permit saiddisplacement of the inner portion of the packer adjacent the supportwithout subjecting said end portion of the fabric to rupture by bendingand shearing strains.

15. A packing head for well pipe comprising a tubular body adapted totake work through its bore, a continuously annular packer having alongitudinally tapered surface, a support for one end of the packer, atapered bore packer contracting piston movable toward said support toaxially compress and radially contract the packer about the work, theinner portion of the packer adjacent said support being dispiaceable,when the packer is radially contracted, into a space between saidsupport and the work, and continuously annular fabric embedded in thepacker and having a projecting end portion attached to said support,said fabric extending longitudinally and inwardly within the packer fromits point of attachment to the support and being spaced substantiallyfurther from the packer bore than from the outside of the packer so asto permit said displacement of the inner portion of the packer adjacentthe support without subjecting said end portion of the fabric to ruptureby bending and shearing strains.

16. A packing head for well pipe comprising a tubular body adapted totake work through its bore, a continuously annular packer, a support forone end of the packer, a packer contracting piston movable toward saidsupport to axially compress and radially contract the packer about thework, the inner portion of the packer adjacent said support beingdisplaceable. when the packer is radially contracted, into a spacebetween said support and the work, and continuously annular fabricembedded in the packer and having a projecting end portion, an annularmember clamping said projecting end portion of the fabric to saidsupport, said fabric being spaced substantially further from the packerbore than from the outside oi the packer so as to permit saiddisplacement of the inner portion of the packer adjacent the supportwithout subjecting said end portion of the fabric to rupture by bendingand shearing strains.

17. A packing head for well pipe comprising a tubular body adapted totake work through its bore, a continuously annular packer having alongitudinally tapered surface, a support for one end of the packer, atapered bore packer contracting piston movable toward said support toaxially compress and radially contract the packer about the work, theinner portion of the packer adjacent said support being displaceable,when the packer is radially contracted, into a space between saidsupport and the work, and continuously annular fabric embedded in thepacker and having a projecting end portion, an annular member againstwhich the end of the packer bears, for clamping said projecting endportion of the fabric to said support, said fabric extendinglongitudinally and inwardly within the packer from its point ofattachment to the support and being spaced substantially further fromthe packer bore than from the outside of the packer so as to permit saiddisplacement of the inner portion of the packer adjacent the supportwithout subjecting said end portion of the fabric to rupture by bendingand shearing strains.

FREDERICK STONE. ALBERT L. STONE.

CERTIFICATE OF CORRECTION.

Patent No. 2, 165 ,815.

June 27 1959.

FREDERICK STONE, ET AL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 6,sec- 0nd column, lines 65 and 7h, claims 1 and 2 respectively, after theword "member" insert exposed to said space and; and that the saidLetters Patout should be read with this correction therein that the samemay conform to the record of the case in the Patent Office.

Signed and sealed this 5th day of September, A. D. 1939.

(Seal) Henry Van Arsdale,

Acting Commissioner of Patents.

the work, the inner portion of the packer adjacent said support beingdisplaceable, when the packer is radially contracted, into a spacebetween said support and the work and continuously annular fabricembedded in the packer and having a projecting end portion attached tosaid support, said fabric being spaced substantially further from thepacker bore than from the outside of the packer so as to permit saiddisplacement of the inner portion of the packer adjacent the supportwithout subjecting said end portion of the fabric to rupture by bendingand shearing strains.

15. A packing head for well pipe comprising a tubular body adapted totake work through its bore, a continuously annular packer having alongitudinally tapered surface, a support for one end of the packer, atapered bore packer contracting piston movable toward said support toaxially compress and radially contract the packer about the work, theinner portion of the packer adjacent said support being dispiaceable,when the packer is radially contracted, into a space between saidsupport and the work, and continuously annular fabric embedded in thepacker and having a projecting end portion attached to said support,said fabric extending longitudinally and inwardly within the packer fromits point of attachment to the support and being spaced substantiallyfurther from the packer bore than from the outside of the packer so asto permit said displacement of the inner portion of the packer adjacentthe support without subjecting said end portion of the fabric to ruptureby bending and shearing strains.

16. A packing head for well pipe comprising a tubular body adapted totake work through its bore, a continuously annular packer, a support forone end of the packer, a packer contracting piston movable toward saidsupport to axially compress and radially contract the packer about thework, the inner portion of the packer adjacent said support beingdisplaceable. when the packer is radially contracted, into a spacebetween said support and the work, and continuously annular fabricembedded in the packer and having a projecting end portion, an annularmember clamping said projecting end portion of the fabric to saidsupport, said fabric being spaced substantially further from the packerbore than from the outside oi the packer so as to permit saiddisplacement of the inner portion of the packer adjacent the supportwithout subjecting said end portion of the fabric to rupture by bendingand shearing strains.

17. A packing head for well pipe comprising a tubular body adapted totake work through its bore, a continuously annular packer having alongitudinally tapered surface, a support for one end of the packer, atapered bore packer contracting piston movable toward said support toaxially compress and radially contract the packer about the work, theinner portion of the packer adjacent said support being displaceable,when the packer is radially contracted, into a space between saidsupport and the work, and continuously annular fabric embedded in thepacker and having a projecting end portion, an annular member againstwhich the end of the packer bears, for clamping said projecting endportion of the fabric to said support, said fabric extendinglongitudinally and inwardly within the packer from its point ofattachment to the support and being spaced substantially further fromthe packer bore than from the outside of the packer so as to permit saiddisplacement of the inner portion of the packer adjacent the supportwithout subjecting said end portion of the fabric to rupture by bendingand shearing strains.

FREDERICK STONE. ALBERT L. STONE.

CERTIFICATE OF CORRECTION.

Patent No. 2, 165 ,815.

June 27 1959.

FREDERICK STONE, ET AL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 6,sec- 0nd column, lines 65 and 7h, claims 1 and 2 respectively, after theword "member" insert exposed to said space and; and that the saidLetters Patout should be read with this correction therein that the samemay conform to the record of the case in the Patent Office.

Signed and sealed this 5th day of September, A. D. 1939.

(Seal) Henry Van Arsdale,

Acting Commissioner of Patents.

